difference between a GE AC440cw & GE C44-9w

[B.Erdmann]

hello,

 

what is the main diferences between these 2 i know the ac4400 is used on the cp & i forget what else & the C44-9w is on CN, UP, BNSF & some others.

 

can some explain for me?

 

thanks

[edbenton]

The AC 44 has AC traction motors and the invertors for them are located behind the cab in a cabinet that extends for around 8 feet I think or so.  The C-44 has dc traction motors nad has its air conditoner located behind the cab.  Beyond that there is really no big difference between the 2 enguines they are both 4400 HP built by GE and were bought by just about every Class 1 you can think of in the 90's BNSF bought both types UP has both types also NS has a offshoot called the C-40-9 some of which have a narrow cab the rest have a wide cab. CN bought only C-44-9W and CP bought AC44's CSX bought AC44 only I think.

[blade]

GE DASH 9-44CW IS IDENTICAL TO DASH 9-40CW SPECIFICATIONS WHICH ARE AS FALLOWS:NORTH AMERICAN CAB.HIAD BOLSTERLESS TRUCKS.2.5 FT LONGER THAN DASH8-40CW.SPLIT COOLING SYSTEM AS INDICATED BY THICKER RADIATOR SECTION.HAND BRAKE CENTERED BELOW RADIATORS.CARBODY DESIGN AND CONFIGURATION OTHERWISE SIMILAR TO DAH9-40CW.

GE AC4400CW IS SAME AS GE DASH 9-44CW EXCEPT STEERABLE TRUCKS ON LATER MODELS.LARGE BOX BEHIND CAB ON LEFT SIDE OF LOCOMOTIVE--CONTAINS INVERTER BANKS AND AC TRACTION CIRCUITRY.VENTED ACESSES PANELS BENEATH THE CAB ON THE RIGHT SIDE OF LOCOMOTIVE.OTHERWISE EXTERNALLY SIMILAR TO DAH 9-44CW.

PLEASE NOTE ALL THE INFORMATION WAS GATHERED BY A BOOK PUBLISHED BY KALMBACH ENTITELED FIELD GUIDE TO DIESEL LOCOMOTIVES WRITTEN BY MR.MCDONNELL.

 

 

[Railfan1]

[Oliver Vazquez]

The DASH 9-44CW's Auxiliary cabinet or box, behind the conductors side is smaller than an AC4400's.

The DASH 9, shown above has the smaller cabinet (to the right of the #4187)

The AC4400CW, shown above, has a larger one. (Next tothe #5676) and it doesn't have the big square vent on it.

The DASH 9, as seen above, also has the AC vents behind the engineer's side of the cab.( Below the #4020 and to the left, you can kind of see 2 vents, those are them)The AC4400CW has the AC vents directly below the engineer's side of the cab. (Directly below the #5600 there are 2 huge vents, those are the AC vents)

[BaltACD]

edbenton

The AC 44 has AC traction motors and the invertors for them are located behind the cab in a cabinet that extends for around 8 feet I think or so.  The C-44 has dc traction motors nad has its air conditoner located behind the cab.  Beyond that there is really no big difference between the 2 enguines they are both 4400 HP built by GE and were bought by just about every Class 1 you can think of in the 90's BNSF bought both types UP has both types also NS has a offshoot called the C-40-9 some of which have a narrow cab the rest have a wide cab. CN bought only C-44-9W and CP bought AC44's CSX bought AC44 only I think.

CSX has about 30 Dash-9's  and approaching 1000 of the AC's

[NorthWest]

I believe that CSX has 50 "C44-9Ws", which are rather interesting. They are sometimes classified as "C44-8Ws", sharing the step well arrangement of the C40-8Ws, as well as some other features, notably the trucks. However, they were built with the C44-9W cooling arrangement and 4400 HP. I think they were built to use up -8 parts, but I'm not sure. I think  CSX has no standard C44-9Ws. 

[beaulieu]

CSX's C44s were built after Dash-8 production had otherwise ended, and before regular Dash-9 production had begun. You could consider them a pre-production model, not having all the features of the Dash-9s.

[NorthWest]

A preproduction model is a good way to identify them.

On an unrelated note, BNSF preproduction ES44ACs have "AC4400EV" written on the cab sides. The radiators are also obvious distinctions from the production model. 

[Will Davis]

To the original question - difference between the Dash 9 and the AC..   Major differences in tractive effort and in dynamic braking effort, pointing up the advantage of the AC traction motor drive.

(Using a 9/93 GE sales brochure...)

The Dash 9 was available with three different horsepower ratings; 4000, 4140 or 4400.  The standard locomotive was rated 109,000 lbs continuous tractive effort, but the "High Tractive Effort Option" (which used 90/19 gear ratio, 42 inch wheels, and had a 65 MPH top speed instead of 70) was rated 118,000 lbs continuous effort.

(Using a similarly dated GE brochure for the AC units....)

The AC4400CW was rated 145,000 lbs continuous effort; only one HP rating offered.

Starting tractive effort, Dash 9 with High Tractive Effort Option, 159,000 lbs.  AC4400CW, 180,000 lbs.

In dynamic brake, the Dash 9 as standard was rated 78,000 lbs braking force peak with the High Tractive Effort package increasing this to 84,000 lbs peak.  The AC4400CW peak braking effort was 98,000 lbs.

Those are some pretty significant differences; I had not myself realized that they were just that pronounced until I got these materials out for this little exercise.

-Will Davis

[JayPotter]

The 180,000-lb starting tractive effort rating for the AC4400CW might be considered the maximum amount of TE that the locomotive is permitted to produce, as opposed to the maximum amount that it is capable of producing.  It reflects the fact that each of the six traction motors is software-limited to producing 30,000 pounds of TE in order to reduce the risk of excessive mechanical stress and electrical load.  If that limit is increased, the maximum amount of TE that the locomotive can produce increases above 180,000 pounds.